Q2 of 65 Page 10

Let us calculate and write the value of k for which –a will be a root the quadratic equation x² + 3ax + k = 0.

Given equation is

It is given that -a is a root of the equation.

Therefore, it must satisfy the equation.

⇒

Hence, the value of k is .

In each of the following cases, let us justify & write whether the given values are the of the given quadratic equation:

and

Let us calculate and write the value of k for which 2/3 will be a root the quadratic equation 7x² + kx – 3 = 0.

If 2/3 and -3 are the two roots of the quadratic equation ax² + 7x + b = 0, then let me calculate the values of a and b.

Let us solve :

3y² – 20 = 160 – 2y²

Questions · 65

1. Quadratic Equations in One Variable

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Let us calculate and write the value of k for which –a will be a root the quadratic equation x2 + 3ax + k = 0.